(19)

(11)

EP 2 102 444 A2

(12)

(88) Date of publication A3: 28.08.2008 (43) Date of publication: 23.09.2009 Bulletin 2009/39 (21) Application number: 07862646.2 (22) Date of filing: 07.12.2007

(51) International Patent Classification (IPC):  E21B 10/42(2006.01) E21B 10/61(2006.01) E21B 10/60(2006.01) (86) International application number: PCT/US2007/025098 (87) International publication number: WO 2008/073307 (19.06.2008 Gazette 2008/25)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR (30) Priority: 11.12.2006 US 874121 P (71) Applicant: BAKER HUGHES INCORPORATED Houston TX 77210-4740 (US)	(72) Inventor: RICHERT, Volker 29229 Celle, Lower Sachsony (DE) (74) Representative: Hano, Christian  v. Füner Ebbinghaus Finck Hano Patentanwälte Mariahilfplatz 3 81541 München 81541 München (DE)